Please refer to this video: https://youtu.be/TRJ4vvSf8YI. For full-sized and tenkeyless keyboard functions, press fn + F10. On the other hand, for the mini or 60% and 65% smaller keyboards: press FN + U. Also, please refer to this article: How to enable Gaming Mode on Razer Blade, keyboard, or network device (Sila).

I knew I would get this answer, but no, that is a completely different function then what is mentioned.

Not referring to gaming mode. That a separate feature listed in the manual. The section I’m referring to is specifically called Keyswitch Optimization, as I clearly stated in my question. 

For some reason, I don’t think this applies to the Deathstalker. I love this keyboard, but the sensitivity is insane. I think the manual has information that has been applied to a bunch of keyboards and they didn't rewrite it for individual models. The PDF isn’t a text document that has been rendered into a PDF document. It is basically an image. Unfortunately, I think that’s a reflection of the documentation that exists in this company. I think this only applies only to keyboards with “analog” keys. In the context of our keyboards, these would be the keys that are pressure-sensitive. Since the Deathstalker has optical keys, I think we are looking at a “digital” or “binary” input; either 1 or 0 for the input. Since there is no value in between, we are out of luck.

I didn’t even think about the fact of optical versus analog lol you may be correct